1. Field of the Invention
This invention relates to a surgical file that is used in a surgical procedure for removing bone or portions thereof from a patient. More particularly, the invention relates to a surgical file for cutting, removing, grinding, shaping and sculpturing bone and to the surgical file construction and the mechanism for imparting reciprocal motion to the reciprocating file of the surgical instrument.
2. Description of Related Art
U.S. Pat. No. 7,390,330 granted to Harp on Jun. 24, 2008 describes a surgical file that has a sundry of applications that may be used by a surgeon for the treatment of certain types of pathology. Essentially, this patent relates to a surgical file that is similar to the surgical file described in the present patent application and the invention described in this patent application patentably distinguishes over the surgical file disclosed in the U.S. Pat. No. 7,390,330 patent ('330), supra while also, obtaining unexpected results for the reasons that will be described herein below. The '330 patent, supra, discloses a shielded reciprocating surgical file system and allows a user to navigate the file into hard to access parts of the patient's body. A transmission mechanism converts rotary motion from a motor into reciprocating motion and pump mechanism and an irrigation system that supplies fluid to the surgical site.
To obtain the reciprocal motion from the rotary motion, the structure disclosed in the '330 patent, supra, utilizes a torus transmission device which may include an integral shaft or a rigidly connected shaft. The torus drive and drive shaft are rotatable about a central rotation axis and has a generally circular or curvilinear cam portion with the torus central axes being at an offset angle. The variable thickness of the torus cam surface produces a hybrid dual or twin torus. As will become evident from the description to follow, the inventive mechanism described in this application provides a far less complicated transmission system for converting the rotary motion to reciprocal motion as will be described in more detail herein below.
The file member of the surgical file instrument includes an elongated angular shaft portion having a blade on the distal end and a tang on the proximal end and is encapsulated in an elongated cylindrical tube of plastic material disposed in an elongated generally “infinity symbol” shaped aperture and having lumens formed therein. The lumens serve to define passageways extending externally of the patient to the surgical site. The distal end of the elongated tube flairs into a generally flat portion with judicious located curvatures that together define a guide for the blade of the file.
As was discussed in the '330 patent, supra, the present invention has utility for many medical procedures that are typically the concern in neurosurgery, orthopedic surgery and plastic surgery, amongst others. For example in neurosurgery, the neruroforamen may need enlargement and the file can be instrumental in removing rigid bony vertebral structure to allow the nerve roots to pass there through. In orthopedic surgery the knee may require sculpturing. And, in plastic surgery bone and tissue sculpturing may be required for nose reshaping and rhinoplasty. The surgical file is efficacious for use in these types of procedures and methodology.